For marinade: In a small food processor combine cilantro, garlic, lime juice, fish sauce, coconut aminos, ginger, turmeric, and peppercorns. Cover; process until smooth.
Prick chicken all over with a small knife. Place chicken in a plastic bag set in a shallow dish. Pour marinade over chicken. Seal bag; turn to coat. Chill at least 2 hours and up to 24 hours.
Remove chicken from marinade; discard marinade. Grill on rack of a covered grill over indirect heat 35 to 45 minutes or until 175 degrees F for wings, legs, and thighs and 50 to 60 minutes or until 170 degrees F for breasts. Brush with coconut milk the last 20 minutes of grilling. To serve, sprinkle with additional cilantro.